ATOMIC SURFACE AND LATTICE STRUCTURES OF AGBR THIN-FILMS

We have studied the surfaces of (001)- and (111)-oriented AgBr thin films by means of the decoration technique and atomic force microscopy (AFM). On {100} surfaces both methods exhibit the complete step structure including steps of atomic height. On {111} surfaces a superstructure is imaged with spacings of about 6 nm. A six-fold symmetry of the superstructure is revealed by gold decoration. The decorating gold nuclei are highly ordered and aligned along the [110] directions of the AgBr lattice. For the first time atomic resolution of the surface lattice is achieved at both {100} and {111} faces by AFM. The imaged lattices of the protrusions on the cubic faces and the octahedral faces with spacings of 0.41 +/- 0.02 nm and 0.42 +/- 0.02 nM, respectively, correspond to the unreconstructed (1 X 1) surfaces.